根据风动潜孔锤反循环钻进技术的特点,借鉴最小动能法推导出风动潜孔锤反循环钻井满足携屑能力的最小注气量和中心通道内最低井底压力,二者耦合得出风动潜孔锤反循环钻井最小注气量模型,结合GQ-320型潜孔锤工程算例,计算出不同机械钻速下最小注气量,并将模型计算结果与现场实测气量值进行比较.结果表明:在地层条件完整或漏失不严重的情况下,风动潜孔锤反循环钻井最小注气量计算值与现场实测值吻合较好；实例井上返岩屑的速度分析与现场未洗井情况一致,验证了模型的可靠性.%According to the characteristics of pneumatic DTH hammer reverse circulation drilling technology, the minimum gas volume flow rate satisfying the minimum capacity of carrying scrap and the minimum bottom hole pressure within the central channel of pneumatic DTH hammer reverse circulation drilling were deduced using the kinetic energy method. Then, the model of the minimum gas volume flow rate of pneumatic DTH hammer reverse circulation drilling was established. Combined with the CQ-320 type DTH hammer practical work, the minimum gas volume flow rates under different penetration rates were obtained and compared with the measured values. The results show that under the condition of formation complete or the loss being not serious, the calculation values of the gas volume flow rate of the pneumatic DTH hammer reverse circulation drilling agree well with the field values. The upward cutting velocity analysis agrees well with the field data, which verifies the reliability of the model.
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